Retaining wall with plastic coated wooden panels

ABSTRACT

A retaining wall ( 10 ) is formed by a series of structural panels ( 18 ) arranged in edge-to-edge relationship, supported by horizontally extending wales ( 16 ) and vertically extending piles ( 14 ). The panels are formed of a rectangular board ( 40 ) with a plastic envelope ( 42 ) adhered to the board. Strips ( 60  and  61 ) are adhered to the plastic material at one edge portion of each panel, with the strips forming protruding lips ( 58  and  50 ) that receive the second edge of an adjacent panel, thereby guiding the new panels into place and forming a barrier to the movement of water and water borne debris between the panels.

CROSS REFERENCE

This application is a continuation-in-part of co-pending U.S. patent application Ser. No. 10/891,930, filed Jul. 15, 2004 in the U.S. Patent and Trademark Office.

FIELD OF THE INVENTION

This invention concerns retaining walls of the type used for retaining the earth at the water's edge of a body of water, particularly where the wall is to be exposed to harsh environmental conditions, such as extreme heat and cold, moisture, insects, abrasion, etc.

BACKGROUND OF THE INVENTION

Barrier walls can be formed of a plurality of elongated vertically oriented piles having their lower extremities driven into the earth to a depth sufficient to support the piles and their associated structural elements. Horizontally extending wales are mounted to the piles, and vertically oriented structural panels are partially driven into the earth adjacent the wales. Usually, the panels have interlocking male and female opposed edges that are used to connect to the edges of the panels together. Also, the male and female edges of the panels are used for guiding the next panel into position in the wall structure by engaging the male and female edges of the adjacent panels as the oncoming panel is driven into the earth. This causes the connected panels to form a continuous barrier wall.

Because of the strength required for the panels when being driven into the earth and the strength required under the load conditions, the panels have to be strong. In the past, panels have been made of wood, and the wood can be cut to specific sizes for providing proper strength characteristics to the wall structure. However, wooden panels are subject to deterioration from marine borers and other insects, and rot and deterioration from impact by other objects. In order to avoid deterioration from rot and marine borers, wooden panels can be chemically treated. This slows the deterioration process of the panels from marine borers but provides the potential hazard of leaching of hazardous chemicals from the panels into the water and adjacent surroundings, possibly causing an environmental hazard. Also, wooden panels tend to shrink and/or swell in response to their environmental conditions. This tends to cause gaps between the panels in the wall structure, allowing water, silt and other undesirable elements to pass with water through the wall structure. In order to avoid the passage of material through the panels, wooden panels have been formed with tongue and groove edges that mate together in an attempt to reduce the ease of passage of the materials between adjacent panels. Another preventive measure is to use additional sheet material that is spread across the panels so as to retard movement of particles through the gaps between panels.

More recently, retaining walls have been formed with metal panels, such as steel or aluminum that are stronger than wood. The metal panels have been formed in cross sectional shapes such as V-shapes, Z-shapes, etc. that provide lateral strength and stability to the panels. This enables the thicknesses of the panels to be reduced substantially so as to conserve on the weight and expense in forming and handling the panels. However, the shaped panels are sometimes considered undesirable because they do not present a flat surface that is more visually and structurally pleasing.

At the present time, the most popular panels for the construction of retaining walls are extruded plastic panels. The panels formed of plastic have good compression strength properties so that they can be driven into the earth, but their lateral strength properties are weaker than the metal panels. In order to provide lateral strength to the panels, the V-shaped and Z-shaped profiles of the panels have been increased and the thickness of the panels has been increased.

While the metal and plastic panels have been successful in avoiding deterioration by marine borers and other insects, the profiles of the panels are still objected to by many since they do not provide a pleasing, less industrial look like the flat panels.

Recently, structural panels have been formed of wooden boards with plastic surfaces that form envelopes about the boards and protect the interior wood from marine borers, abrasion, moisture, etc. In some instances, the plastic material has been applied by spraying it onto the surface of wooden boards, as shown by U.S. Pat. No. 6,135,675, or by vacuum extrusion of plastic material onto the surface of the wooden boards, as disclosed in co-pending U.S. patent application Ser. No. 10/891,930. By providing the protective plastic surfaces to the wooden boards, there has been a beneficial result of reduction in deterioration of the panels from marine borers, better moisture control of the interior wooden boards of the panels, and reduced deterioration from impact, abrasion, and other external sources.

However, the known panels made of wooden boards with plastic exteriors have not been successful in forming panels that are connected edge-to-edge to form a strong and continuous barrier that retards the movement of water and water-borne particles through the wall structure. U.S. Pat. No. 5,360,295 discloses the use of plastic tongue and groove edge attachments that are mechanically attached to the opposed edges of wooden boards, requiring attachments to both edges of the boards. This requires the manufacture of the two plastic edge attachments and the additional separate functions of attaching both of the edge attachments to the boards. Also, the tongues and grooves are formed with voids between the wood and the plastic material that forms the tongues and grooves, thereby forming spaces that can receive and hold water. The retention of water between the boards and their tongues at one edge of the panels and/or between the boards and their grooves at the other edge of the panels introduces the hazard of freezing of the retained water in the panels in cold weather and deterioration of the adjacent surfaces of the plastic and the wood of the panels. Also, PVC plastic, for example, is about one third as strong as wood and the connection of a plastic a tongue protruding from a board into a plastic groove also protruding from the adjacent board is a connection of the weakest portions of the boards that is more likely to fail under lateral stress than with board-to-board connection or with only one connector between adjacent boards.

Thus, it would be desirable to provide an improved retaining wall assembly for use in harsh environmental conditions that utilizes wooden boards that are resistant to marine borers and that have edges that fit together for ease in aligning and connecting the panels in edge-to-edge relationship when being installed and which reduce the likelihood of movement of water and water borne material between the panels.

It would be desirable to produce structural panels for use in retaining walls and the like that are formed of wood and covered in an air tight plastic envelope with a groove formed at only one edge and no matching tongue at the other edge, with the groove sized and shaped to mate with the rectangular end of the panel.

Another object of this invention is to provide an improved panel for use in retaining walls and the like that are formed of wood and coated with plastic and have an improved connection feature at its edges that is strong, reliable and inexpensive to form and maintain.

Another object of this invention is to provide wooden panels covered with plastic and that include a groove formed at one edge that fits the conventional rectangular edge of the adjacent panel with a strong fit and that does not require the presence of a tongue at the edge of the adjacent panel.

Other objects, features and advantages of the present invention will become apparent upon reading the following specification, when taken in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a section of a retaining wall, showing a vertical pile, a horizontal wale, and a series of panels supported by the wale, with a section of the plastic envelope of the pile removed to illustrate that the core of the pile is formed of wood, and with a portion of the anchor rod removed.

FIG. 2 is an end cross sectional view of adjacent panels of FIG. 1, showing on one side of the figure how the panels are attached to each other, and showing on the other side of the figure the panels expanded from each other to indicate how the panels fit in edge-to-edge relationship.

FIG. 3 is a side elevational view of adjacent panels showing the last of the panels being moved vertically into position and guided by the lips of the previously positioned panel.

FIG. 4 is a perspective view of an edge portion of a panel that has been installed in the earth, showing in dash lines how the next adjacent panel will be installed.

FIG. 5 is a schematic illustration of how the connector lips are formed on the structural panels.

FIG. 6 is a perspective view of a wall formed with the structural panels of the preceding figures, but with the panels oriented horizontally in the wall structure.

DETAILED DESCRIPTION

Referring now in more detail to the drawings, in which like numerals indicate like parts throughout the several views, FIG. 1 illustrates a retaining wall 10 that has been assembled for placement between a body of water 11 and a land mass 12, for separating the water from the land. While only a portion of the retaining wall is illustrated, it will be seen that it includes a plurality of vertical piles 14, horizontally extending wales 16, and a plurality of elongated, vertically oriented structural panels 18 placed in edge-to-edge relationship. The piles 14 are oriented vertically so that they can be driven downwardly through the water 11 and into the earth below so that the lower end portions of the piles are embedded in the earth and remain stabilized by the earth. Wales 16 are arranged in end-to-end relationship and extend horizontally between the piles 14 and the land mass 12. The structural panels are elongated and extend vertically. The structural panels are driven downwardly so that their lower extremities are driven through the water into the earth below. The wales are used as a guide to orient the structural panels as they are being driven and the wales support the panels when the retaining wall structure is completed.

The piles, wales and structural panels preferably are made of wood that is treated with chemicals for reducing the rate of deterioration of the wood due to harsh environmental conditions, and due to marine borers and other insects. Additionally, the piles and wales and panels are coated with plastic, such as polyethylene, polyvinyl chloride, or wood flour composites, by extrusion, spraying, or other application methods. The plastic coatings may cover the entire exterior surface of the work products, including sides, edges and the end surfaces thereof. An example of a method of extruding plastic envelopes about piles, wales and panels is disclosed in co-pending U.S. patent application Ser. No. 10/891,1150.

Wale 16 includes a wooden core 20 that is covered with the plastic envelope. Pile 14 is wooden, as illustrated at 22 and the plastic envelope 24 is applied to the wooden core. The panels 18 are wood boards 40 with plastic coating forming the envelope 42.

A tie rod 26 extends through the piles 14, its wale 16, and the adjacent structural panel 18. Tie rod 26 includes an enlarged head 27 and a washer 28 on the outside surface of the pile to spread the forces applied by the tie rod to the pile. Helical threads 29 are formed on the tie rod at its distal end. An anchor rod 30 includes helical threads 31 at one end and its other end is connected to an anchor, such as poured concrete 32. A turnbuckle 34 connects the helical threads 29 and 31 together, thereby adjustably connecting the anchor 32 by the anchor rod 30, turnbuckle 34, tie rod 26, to the pile 14 of the wall structure 10, thereby stabilizing the wall structure in its upright orientation.

FIGS. 2-4 show the structural panels 18. Each structural panel is formed of a wooden board or plank 40 that is optionally treated with chemicals that tend to reduce the rate of deterioration of the boards. The boards 40 are rectangular in cross-section and are elongated. For example, a typical board used as a structural panel may be from one to four inches in thickness and from four to twelve inches in width. Other dimensions are available, depending on conditions such as the size of the boards needed at the job site, the supply of stock available to the manufacturer of the panels, and the price of the product. The example illustrated in FIG. 2 is a board that is two inches in thickness and eight inches in width, and is rectangular in cross-section and would be of a length as may be desired at the site where it is to be constructed, for example ten feet in length.

The board 40 of the structural panel 18 is clad in a plastic envelope 42, with the cladding being in abutment with the surfaces of the board. For example, opposed side surfaces 44 and 45 of the board are covered by side sheets 46 and 47 of the plastic envelope, whereas opposed edge surfaces 48 and 49 are clad by edge sheets 50 and 51. The plastic envelope 42 will conform in shape to the exterior surfaces of the board 40, which will be rectangular. The thickness of the plastic may vary, depending upon the type of plastic that is to be used. An example of an acceptable thickness of a polyvinyl chloride envelope is 0.070 inches, with a variance of plus or minus 0.015 inches.

Edge connector means 54 are applied to a first edge surface 55 of the structural panel 18, with the opposed second edge 56 not requiring edge connector means. As shown in FIG. 2, the edge connector means 54 includes a pair of lips 58 and 59 that overhang the first edge 55. The lips 58 and 59 are formed by the application of strips 60 and 61 to the opposing side sheets 46 and 47, with a first longitudinal segment 62 of each strip adhered to the side sheets 46 and 47, and a second longitudinal segment 63 protruding on laterally beyond the side sheets to form the lips 58 and 59. The lips 58 and 59, together with the first edge 55 of the structural panel, form a U-shaped recess 65, with the lips being spaced apart a distance substantially equal to the thickness of the board 40 and the thicknesses of its side sheets 46 and 47.

The second edge 56 of the structural panel does not have a tongue or groove, but remains with the conventional double right angle edge or “right angle edge.” When the second or right angle edge 56 of a structural panel 18 is placed adjacent the first edge 55 of a panel that includes the edge connector means 54, the second edge 56 fits snugly within the U-shaped recess 65, and the lips 58 and 59 extend about a portion of the adjacent side sheets 46 and 47 of the plastic envelope 42. The lips 58 and 59 cover the crack between the adjacent panels.

As shown in FIGS. 3 and 4, when a series of panels have been driven into the earth 67 below the water 11, the new panel 18B will have its second edge 56 received in the U-shaped recess 65 formed by the lips 58 and 59 of the previous panel. The lips guide the new panel 18B as it is being driven in the direction indicated by arrow 68, so that the lips 58 and 59, as well as the first edge 55 of the previously installed structural panel guide the new panel 18B as it is being driven downwardly. This tends to guide the panels so that they will be connected together in a straight wall.

After the panels have been installed as indicated in FIG. 1, the strips 60 and 61 at the first edge 55 of each panel overlie the adjacent edges of the adjacent panels, thereby tending to block the passage of water and water-borne materials between the adjacent panels.

Typically, the process of forming the structural panels 18 involves the cladding of the panels with the plastic envelopes. As stated previously, this can be performed by a vacuum extrusion process described in co-pending U.S. patent application Ser. No. 10/891,930, which is incorporated herein by reference in its entirety. Generally, the process may include vacuum extrusion of the plastic about the boards so that the boards are enveloped by the plastic and the vacuum draws the plastic into direct contact with the boards, thereby substantially eliminating air from between the plastic and the boards.

Once the panels have been clad with plastic, the strips 60 and 61 can be extruded into position on and adhered to the panels. For example, FIG. 5 shows in schematic form an extruder 70 that includes die openings 71 and 72 that are arranged in spaced relationship in accordance with the anticipated thickness of the structural panel 18 that includes the board 40 and its plastic envelope 42 with its side sheets 46 and 47 and its edge sheets 50 and 51 previously applied thereto. The extruder 70 is shaped so that it lays down the strips 60 and 61 that overlap the first edge 55 of the structural panel 18. The strips are formed of a material that is compatible with the material of the plastic envelope of the board, such as polyvinyl chloride, and the temperature and consistency of the strips 60 and 61 is such that the strips become adhered to the plastic material of the side sheets 46 and 47 of the structural panel. The strips 60 and 61 are cooled so that they are cured in place and are firmly adhered to the side sheets 47 and 48 at the edge sheets 50 and 51 of the plastic envelope 42. The over hanging segments of the strips form the lips 58 and 59 as previously described.

While the inventors have disclosed the strips 60 and 61 being attached by extrusion onto the panels 18, it is anticipated that other connection methods may be used.

With the strips 60 and 61 being positioned on the panels the overlying portions of the strips form the lips 58 and 59 of the structural panels, and the lips function to guide the new panel, such as new panel 18B of FIG. 3, as it is being moved downwardly as indicated by arrow 68 into edge abutment with respect to previously installed structural panel 18A. In addition, the strips 60 and 61 retard the movement of water and water borne items through the panels. Moreover, the panels, being in edge-to-edge juxtaposition, with the edge of one panel supported by the U-shaped recess 65 between the lips of an adjacent panel, form a stable wall structure.

It will be noted that the structural panels 18 have only one pair of edge connector lips 58 and 59 formed on one edge structure 51. The opposing edge structure 50 is free of any reconfiguration and keeps its original rectangular shape with the pair of right angle corners. This reduces the manufacturing expense and reduces the likelihood of error in the manufacturing process.

FIG. 6 shows another wall structure 75 formed of the structural panels 18. The panels are oriented horizontally, stacked upon one another, with their first edges that have the protruding lips facing vertically and in registration with the rectangular second edge of the adjacent panel. The panels may be formed of equal length and their ends aligned. A series of piers such as upright I-beams 77 are driven into the earth and/or supported by poured concrete 78 in lateral alignment with each other with their oppositely facing grooves 80 facing the next adjacent I-beams. The structural panels are assembled with their opposed ends 81 received in the grooves 80 of adjacent I-beams. Other types of piers may be used if desired.

The overlapping lips 58 and 59 of the structural panels function to keep the panels 18 in a wall structure aligned and tend to minimize effects of lateral displacement of the panels due to warping of the panels or engagement of lateral forces against the panels, both when the panels are oriented vertically or horizontally.

While the piles 14 and panels 18 of FIGS. 1-5 are disclosed as being vertically oriented, and the wales and panels horizontally oriented, and the piles of FIG. 6 are disclosed as being vertically oriented and the panels horizontally oriented, it will be understood that these and other structural components may not be precisely installed and the terms such as “vertically”, “horizontally” and “upright” are to generally describe the orientation of the components of the wall structure with respect to one another.

Although a preferred embodiment of the invention has been disclosed in detail herein, it will be obvious to those skilled in the art that variations and modifications of the disclosed embodiment can be made without departing from the spirit and scope of the invention as set forth in the following claims. 

1. A structural panel for forming vertical walls in harsh environments comprising: an elongated board rectangular in cross section and having opposed side surfaces and opposed first and second edge surfaces, a plastic coating extending about and along and applied to said elongated board for shielding said board from contact with the environment adjacent said board, a pair of plastic strips narrower than the side surfaces of said board and extending along the length of the board at the opposed side surfaces of said board and extending beyond said first edge surface, said plastic strips each having one elongated segment applied to one of said broad side surfaces of said board and an adjacent elongated segment extending beyond the first edge surface of said board and forming a pair of parallel lips said parallel lips together with said first edge surface of said board forming a groove sized and shaped to receive the opposed second edge surface of a duplicate structural panel, such that duplicate ones of said structural panels can be mounted in edge-to-edge nested connected relationship to form a continuous wall structure without openings at the edge surfaces of the wall structure.
 2. The structural panel of claim 1, wherein: said plastic strips are heat sealed to said plastic coating of said board.
 3. The structural panel of claim 2, wherein said board further includes ends, and said plastic coating extends about said ends.
 4. The structural panel of claim 3, wherein: said lips are spaced from each other a distance equal to the thickness of said board and said plastic coating on the opposed side surfaces of said board.
 5. The structural panel of claim 4, and further comprising: a series of said structural panels arranged in upwardly extending edge-to-edge relationship each with its groove receiving a second edge of an adjacent structural panel. at least some of said panels partially embedded in the earth, at least one wale extending horizontally across said series of panels, a water impervious plastic coating applied to said wale, at least one piling extending upwardly across said wale and partially embedded in the earth, a water impervious plastic coating applied to said piling, such that the piling supports the wale and the wale supports the structural panels and forms a structural wall that is impermeable to marine borers.
 6. The structural panel of claim 1, wherein: said board is formed of natural wood and said plastic coating is water impervious.
 7. The structural panel of claim 6, wherein: said plastic coating is characterized by having been extruded onto said board.
 8. The structural panel of claim 6, wherein: said plastic coating is characterized by having been sprayed onto said board.
 9. The structural panel of claim 1, wherein: said plastic strips are characterized by having been extruded onto said plastic coating.
 10. The structural panel of claim 1, wherein: said plastic strips are adhered to said plastic coating.
 11. The structural panel of claim 7, wherein: said opposed side surfaces of said structural panel are flat and parallel to each other, with said opposed side surfaces being of greater width than said opposed edge surfaces.
 12. The structural panel of claim 1, wherein: a series of said structural panels are arranged with their edges juxtaposed and with the plastic strips covering the juxtaposed edges without protruding between said juxtaposed edges.
 13. The structural panel of claim 1, wherein: a series of said structural panels are arranged with their edges in contact with one another without said lips projecting between said structural panels.
 14. A structural panel for forming vertical walls in harsh environments comprising: an elongated board rectangular in cross section and having opposed side surfaces and opposed first and second edge surfaces, a water impermeable coating surrounding and extending along and applied to said elongated board for shielding said board from contact with the environment adjacent said board, a pair of strips extending along the length of said coating at the opposed side surfaces of said board and extending beyond said first edge surface, said strips each extending beyond the first edge surface of said board and forming a pair of parallel lips, said parallel lips together with said first edge surface of said board forming a groove sized and shaped to receive the opposed second edge surface of a duplicate structural panel, such that duplicate ones of said structural panels can be mounted with their second edges and the grooves of an adjacent panel in interfitting relationship to form a continuous wall structure with the strips covering the openings between the structural panels.
 15. The structural panel of claim 14, and further comprising: a series of said structural panels arranged in upwardly extending edge-to-edge relationship each with its groove receiving a second edge of an adjacent structural panel, at least some of said panels partially embedded in the earth, at least one wale extending horizontally across said series of panels, and at least one piling extending upwardly across said wale and partially embedded in the earth.
 16. The structural panel of claim 15, and further comprising: a water impervious plastic coating applied to said wale, and a water impervious plastic coating applied to said piling.
 17. A retaining wall assembly comprising: a series of wall panels each of duplicate cross sectional shape and covered by water impervious coating and of rectangular shape with opposed side surfaces and opposed first and second edge surfaces, each said wall panels including a pair of lips extending about said first edge surface spaced from each other a distance corresponding to the width of said wall panel for receiving the second edge surface of a duplicate wall panel, said series of wall panels oriented vertically each with their second edges received between said pair of lips of an adjacent wall panel and partially embedded in the earth, at least one wale extending normal to and in supportive relationship with said series of wall panels, and at least one pile oriented vertically and partially embedded in the earth and positioned in supportive relationship with said wales, such that the wall panels are arranged in edge surface to edge surface with the lips of each panel overlapping the spaces between the panels without requiring a non-rectangular shape of the adjacent panel.
 18. The retaining wall assembly of claim 17, and further comprising: a water impervious plastic coating applied to said wale, and a water impervious plastic coating applied to said piling.
 19. The retaining wall assembly of claim 18, wherein: said water impervious coatings are characterized by having been extruded onto said panels, said wale and said pile.
 20. A structural panel for use in constructing walls that is formed of a rectangular wooden board having opposed first and second edges, said board covered in an air tight plastic envelope with the plastic envelope forming a groove at said first edge of said board and no matching tongue at the second edge of said board, with the groove sized and shaped to mate with the second edge of a duplicate structural panel.
 21. The structural panel of claim 20 wherein said air tight plastic envelop is characterized by having been formed by vacuum extrusion.
 22. A wall structure comprising a series of upright elongate supports spaced from one another, and a plurality of said structural panels of claim 20 oriented horizontally between and supported by adjacent ones of said upright supports with the grooves of at least some of the structural panels in registration with an adjacent structural panel.
 23. A wall structure of claim 22, wherein said upright elongate supports comprise I-beams with oppositely facing grooves, with said structural panels received in said grooves of said I-beams. 